.model{
    position: fixed;
    top:0;
    left:0;
    width:100%;
    height:100%;
    background-color: rgba(0,0,0,.5);
    display: flex;
    justify-content: center;
    align-items: center;
    .model_box{
        width:500px;
        padding:20px;
        background:#fff;
    }
}